Extruded metal stock, which can be coiled into rings or coils, is hereinafter referred to as "wire" and will be understood to include extruded rod as well as structural shapes and profiles, i.e. rod or wire of any cross section including circular cross section, prismatic cross section and structural shape cross section, as well as tubular rod or stock.
For details of hot metal extrusion, reference may be had to the following works: "Strangpressanlagen mit Hilfs- und Folgeeinrichtungen fur Kupferwerkstoffe"; Dieter Veltjens, Metall 29 (1975) 11, pages 1110 to 1117, "Strang-und Rohrpressanlagen fur die Schwermetallindustrie"; F. J. Zilges, Metall 36 (1982) 4, pages 439 to 443, "Hauptkriterien bei der Auslegung einer Strangpressanlage fur Schwermetall".
Whether the cross sections of the extruded stock are solid or hollow, to the extent that they are to be coiled in rings or coiled in coiler apparatus, they are referred to "wire" herein and it is not uncommon in the cooling of such wire to coil the wire into so-called wire rings and then transport the wire rings through the coiling line in protective tubs. Following the cooling operation, the wire rings may be subjected to further processing or treatment, for example, to a binding of the coils or wire rings, to collection of the wire rings and/or to the delivery of the wire rings for some other purpose. For such processing, the wire rings may be separated from their protective tubs and generally the protective tubs are reused.
It is, therefore, a common practice to coil the wire rings in the protective tubs, to displace the tubs containing the respective wire rings along the cooling path and at the end of the cooling path to remove the wire rings from the protective tubs, return the tubs to the coiling stations and pass the wire rings onto the stations for subsequent processing.
In the past, during the course of separation of the wire rings from their respective protective tubs, there has been a tendency for the wire rings or coils to loosen and to lose the compact form which is desirable for the coil or ring.